I'm using my custom yolov3 trained to detect one class.

I converted the Yolo weights to TensorFlow.

then when i run this command
python object_tracker.py --video ./data/video/XXX.mp4 --output ./outputs/demo2.avi --model yolov3 --weights ./checkpoints/yolov3 --info True --count True --info True

in the first frame, I get a perfect result.

Frame #: 1
Objects being tracked: 41

after that, it won't detect anything and the objects being tracked stays zero for the rest of the video.

what could cause this issue?

thanks in advance.